Correction: A previous version of this story misidentified the group with which Michelle Obama will be announcing a partnership. It is the Boys and Girls Club, not Big Brothers Big Sisters.

First lady Michelle Obama talks with Sophia Rose Stewart-Chapman, of New York's Little Red School House, in front of a color-by-numbers mural featuring the slogan for WAT-AAH!, a line of bottled water targeted to kids and teens, at the New Museum, in New York, Thursday, Feb. 20, 2014. (Richard Drew/AP)

Michelle Obama is going from silly to serious this week in a continuation of her campaign against childhood obesity, which is entering its fifth year.

Monday, she posted a video of herself playing the straight foil to comedian Will Ferrell’s antics while conducting a mock focus group with children discussing their favorite vegetables and dance tunes.

Tuesday, she will return to food policy and plans to announce partnerships with major after-school programs, including the Boys and Girls Club and the National Recreation and Park Association to ensure that healthy foods, water and periods of physical activity are accessible to kids after school and that sugar-sweetened beverages and unhealthy pastries are banned. The after-school groups, along with the YMCA — which already partners with the first lady’s program — care for more than 5 million children.

“We know out of school time is a vital time for kids on so many levels. This is a time where a lot of kids, certainly if it weren’t for these programs, have very little structure and very little oversight,” said Sam Kass, a White House chef and executive director of the first lady’s Let’s Move campaign. “If kids spend all day drinking sugary drinks and eating a bunch of chips and candy bars, they are going to go home and not really be that interested in dinner.”

Obama will travel Tuesday to Miami to visit an after-school program. She’ll be introduced by Amy Poehler, who stars in “Parks and Recreation” as a mid-level bureaucrat.

Before Florida, the first lady, along with Agriculture Secretary Tom Vilsack, will tout other changes in schools, including the nationwide expansion of free-lunch and breakfast programs that was authorized under the Healthy Hunger Free-Kids Act passed in 2010. It will make federally subsidized meals available to all school children in communities in which more than 40 percent of children qualify for free lunch.

Obama and Vilsack also plan to unveil a study that shows 90 percent of school districts are complying with the federal government’s tougher nutritional standards for school lunches, for which the first lady lobbied. Studies by USDA showed that as recently as 2007, fewer than a quarter of school districts met the government’s standards.

“The meals have gotten a lot better, not only in terms of nutritional quality, but also in appealing to kids, making sure it’s food that kids want to eat,” said Margo Wootan, director of nutrition policy for the Center for Science in the Public Interest.

The high compliance rate comes with an asterisk: Some of the federal nutrition standards will not go into effect until the 2014-15 school year. For the next academic year, elementary schools will need to lower sodium levels to 1,230 milligrams at lunch to meet nutrition standards. By the 2022-23 school year, the sodium must be down to 640 milligrams during lunch. By this coming academic year, schools will need to meet a new standard for whole grains: The primary ingredient, whether in bread or pasta, must be whole grain. That means no white bread, no white-flour pasta and no white rice. For the past two academic years, schools could meet the nutrition standard if only half of the products were majority whole grain.

While the compliance percentage may drop next year as a result of the tougher standards, Wootan says it remains a “badge of honor” for school districts to be certified for the 6-cent federal reimbursement, which they only receive if they meet the nutrition standards. It tells parents the school is serious about childhood nutrition.

“I think the incentive to get additional reimbursement for school lunches has been much better than I ever expected.” Wootan said. “It’s been a rallying cry for schools and state agencies to get all districts to comply” with the nutrition standards.

USDA is also preparing to write regulations on the marketing of food to children during the school day, which will encourage schools to remove posters, paper cups and logos on vending machines that do not meet health standards. If a school’s cafeteria menu board or sports score board advertises a full-sugar soda, administrators will be asked to replace them in time.

Comedian Will Ferrell learns a thing or two about healthy eating from a group of young kids and Michelle Obama in a new video for the first lady's anti-obesity campaign, "Let's Move." (YouTube: LetsMove)

“We’re trying to build as much consistency into the school day as possible,” an administration official said.